Emerging metropolitan optical networks are based on optical cross-connects (OXCs) controlled by internet protocols (IPs). Both elements perform the critical task of optical bandwidth provisioning. These networks currently provide end-to-end circuit-switched bandwidth allocation, through routing protocols like Open Shortest Path First (OSPF), and through signaling protocols like Multi-Protocol Label Switching (MPLS). The increasing needs for greater network connectivity, and efficient bandwidth utilization require more dynamic bandwidth provisioning schemes such as optical burst-switching (OBS) (see C. Qiao, and M. Yoo, “Choices, features and issues in optical burst-switching”, SPIE Optical Networks Magazine, vol. 1, pages 36–44, April 2000). However, this potential evolution does not change the need for high-quality wavelength-switched optical service in the near to medium term. In this context, it is appropriate to design optical switching paradigms capable of efficiently supporting both types of services. However, the design of a common switch platform for wavelength-switching and optical burst-switching (OBS) raises problems, because of their quite different provisioning time-scales. In wavelength-switching, lightpaths are provisioned for hours, days or even months, while in optical burst-switching (OBS) bandwidth is reserved on burst time scales, which are measured in sub-milliseconds units. State of the art optical cross-connects (OXCs) built with micro-electro-mechanical systems (MEMS) technology may have cross-connection latencies expressed in tens of milliseconds (see N. R. Jankowski, C. Bobcowski, D. Zipkin, R. R. Krchnavek, and R. Chamberlain, “MEMS-based optical switch design for reconfigurable fault-tolerant optical backplanes”, Proceedings of the 6th International Conference on Parallel Interconnects, pages 149–156, October 1999). These devices certainly have enough agility to support wavelength-switching, but cannot establish optical cross-connections on a per-burst basis as it is required by optical burst-switching (OBS).
In view of the foregoing, it would be desirable to provide optical wavelength-switching and optical burst-switching techniques for routing data within an optical network which overcome the above-described inadequacies and shortcomings.